Research Topics
- Spectral Theory
- of selfadjoint operators,
second order elliptic differential operators on Euclidean spaces and manifolds,
Laplace(-Beltrami) operators, Schrödinger operators, discrete Schrödinger operators
and more general finite difference operators on lattices and general groups and graphs
- Schrödinger operators
- selfadjointness, spectral theory, behaviour of eigensolutions,
low-lying eigenvalues, Allegretto-Piepenbrink theory for general operators
- Random operators modelling disordered systems
- e.g. random Schrödinger operators, Anderson models, random Hamiltonians with correlations,
quantum percolation models, general percolation Hamiltonians
- Mathematical theory of Anderson localisation
- proof of localisations via multiscale analysis and the fractional moment method,
Wegner estimates, Lifschitz tails and initial scale estimates,
decoupling properties of random operators,
non-monotone parameter dependence of operators
- Ergodic Theory
- in particular as a tool to study the integrated density of states,
Banach-space valued ergodic theorems, uniform approximation via ergodic theory
Percolation theory
- percolation on Cayley graphs, sharpness of the phase transition, distribution of the cluster size,
Laplacians on percolation clusters
- Asymptotic aspects of geometric group theory
- random walks on Cayley graphs, quasi-isometries, Laplacians on graphs,
their spectral distribution function, eigenfunctions
See also the web page of the
Emmy-Noether-Project.